Buggy code:
public class HttpRequestHdr { private static final Logger log = LoggingManager . getLoggerForClass ( ) ; private static final String HTTP = "http" ; private static final String HTTPS = "https" ; private static final String PROXY_CONNECTION = "proxy-connection" ; public static final String CONTENT_TYPE = "content-type" ; public static final String CONTENT_LENGTH = "content-length" ; private String method = "" ; private String paramHttps = "" ; private String url = "" ; private String version = "" ; private byte [ ] rawPostData ; private final Map < String , Header > headers = new HashMap < String , Header > ( ) ; private final String httpSamplerName ; private HeaderManager headerManager ; public HttpRequestHdr ( ) { } public HttpRequestHdr ( String httpSamplerName ) { } public byte [ ] parse ( InputStream in ) throws IOException { } private void parseFirstLine ( String firstLine ) { if ( HttpRequestHdr . log . isDebugEnabled ( ) ) { HttpRequestHdr . log . debug ( ( "browser<seq2seq4repair_space>request:<seq2seq4repair_space>" + firstLine ) ) ; } StringTokenizer tz = new StringTokenizer ( firstLine ) ; method = getToken ( tz ) . toUpperCase ( Locale . ENGLISH ) ; url = getToken ( tz ) ; version = getToken ( tz ) ; if ( HttpRequestHdr . log . isDebugEnabled ( ) ) { HttpRequestHdr . log . debug ( ( "parser<seq2seq4repair_space>input:<seq2seq4repair_space>" + firstLine ) ) ; HttpRequestHdr . log . debug ( ( "parsed<seq2seq4repair_space>method:<seq2seq4repair_space>" + ( method ) ) ) ; HttpRequestHdr . log . debug ( ( "parsed<seq2seq4repair_space>url:<seq2seq4repair_space>" + ( url ) ) ) ; HttpRequestHdr . log . debug ( ( "parsed<seq2seq4repair_space>version:" + ( version ) ) ) ; } if ( getMethod ( ) . startsWith ( CONNECT ) ) { paramHttps = url ; } if ( url . startsWith ( "//" ) ) { url = ( ( ( HttpRequestHdr . HTTPS ) + ":////" ) + ( paramHttps ) ) + ( url ) ; } if ( IMPL_JAVA . equals ( httpSamplerName ) ) { HttpRequestHdr . log . debug ( ( "First<seq2seq4repair_space>Line:<seq2seq4repair_space>" + ( url ) ) ) ; return ; } try { URI testCleanUri = new URI ( url ) ; if ( HttpRequestHdr . log . isDebugEnabled ( ) ) { <START_BUG> HttpRequestHdr . log . debug ( ( "Successfully<seq2seq4repair_space>built<seq2seq4repair_space>URI<seq2seq4repair_space>from<seq2seq4repair_space>url:" + ( url ) ) ) ; <END_BUG> } } catch ( URISyntaxException e ) { HttpRequestHdr . log . warn ( ( ( ( "Url<seq2seq4repair_space>'" + ( url ) ) + "'<seq2seq4repair_space>contains<seq2seq4repair_space>unsafe<seq2seq4repair_space>characters,<seq2seq4repair_space>will<seq2seq4repair_space>escape<seq2seq4repair_space>it,<seq2seq4repair_space>message:" ) + ( e . getMessage ( ) ) ) ) ; try { String escapedUrl = ConversionUtils . escapeIllegalURLCharacters ( url ) ; if ( HttpRequestHdr . log . isDebugEnabled ( ) ) { HttpRequestHdr . log . debug ( ( ( ( ( "Successfully<seq2seq4repair_space>escaped<seq2seq4repair_space>url:'" + ( url ) ) + "'<seq2seq4repair_space>to:'" ) + escapedUrl ) + "'" ) ) ; } url = escapedUrl ; } catch ( Exception e1 ) { HttpRequestHdr . log . error ( ( ( ( "Error<seq2seq4repair_space>escaping<seq2seq4repair_space>URL:'" + ( url ) ) + "',<seq2seq4repair_space>message:" ) + ( e1 . getMessage ( ) ) ) ) ; } } HttpRequestHdr . log . debug ( ( "First<seq2seq4repair_space>Line:<seq2seq4repair_space>" + ( url ) ) ) ; } private int parseLine ( String nextLine ) { } private HeaderManager createHeaderManager ( ) { } public HeaderManager getHeaderManager ( ) { } public String getContentType ( ) { } private boolean isMultipart ( String contentType ) { } public MultipartUrlConfig getMultipartConfig ( String contentType ) { } public String serverName ( ) { } public int serverPort ( ) { } public String getPath ( ) { } public String getUrl ( ) { } public String getMethod ( ) { } private String getToken ( StringTokenizer tk ) { } public String getUrlWithoutQuery ( URL _url ) { } public String getHttpSamplerName ( ) { } public byte [ ] getRawPostData ( ) { } public String getProtocol ( HTTPSamplerBase sampler ) { } }

Fix:
HttpRequestHdr . log . debug ( ( ( ( "Successfully<seq2seq4repair_space>built<seq2seq4repair_space>URI<seq2seq4repair_space>from<seq2seq4repair_space>url:" + ( url ) ) + "<seq2seq4repair_space>=><seq2seq4repair_space>" ) + ( testCleanUri . toString ( ) ) ) ) ;